High-speed revolving-hook sewing-machine.



R. K. HOHMANN.

HIGH SPEED REVOLVING HOOK SEWING MACHINE. APPLICATION FILED MAR. 20,1913.

1,096,369. Patented May 12, 191% 6 SHEETSSHEET l.

J5 mull";

. MZZ ZW QFAL R K. HOHMANN. IGH SPEED REVOLVING HOOK SEWING MACHINE.

APPLICATION FILED MAR. 20

Patented May 12, 1.?14.

R. K. HOHMANN. HIGH SPEED REVOLVING HOOK SEWING MACHINE. APFLIVG.A TIONFILED MAR. 20, 1913.

Patented May 12, 1914.

6 SHEETS-SHEET 3.

SAX/01mm R. K. HOHMANN. HIGH SPEED REVOLVING HOOK SEWING MACHINE. vAPPLICATION FILED 11,512.20, 1913. 1 05136 369, Patented May12,191

6 $HEETS-SHEET 4.

R. K. HOHMANN.

HIGH SPEED REVOLVING HOOK SEWING MACHINE. APPLICATION FILED MAR. 20,1913.

1,096,369. Pa ented Mayl2,1914.,

e SHEETS-SHEET 5.

Patented m 12, 1914.

6 SHEETS-SHEET 6.

R. K. HOHMANN. HIGH SPEED REVOLVING HOOK SEWING MACHINE. APPLICATIONFILED MAR. 20, 1913.

7 7% 99 m l/zflavd W30 .Mf YS- @FFEIQE GALIFOILNIA.

' Jfl'lJG-DIACHINE.

un pufleys cal-r5196. by the tw sha ts, L ii" will be vbserved that thepulley on ww er 15111111, 10 is smaller than that on noportens beingsuch as 10 two revolutions for the-shaft 6. urward end a rotary has inthe form shown is n m h) brad-zen as "possible unnecessar of the casmgLion on 112:1 i 3 pin tu,

flusad from t A bail on standn in the .w W 5 116" H therewith :mlfleeting as; town-t mbbin 19 mad-'3 mu 1 larger than tin m rota 3 hooknacpmos angle innmmt of thread. thus racim You! Juwnand 0f H1 theedge ofthe bol'ibin and being curved in can pass. A spring 30 of any suitableconstruetion is preferably used in the back of the casing around theshaft 23) to press the bobbin out against the retaining member 25 so asto hold it firmly in position preventing rattling, and this spring maybe made in the shape of a thin plate as shown in Figs. 5 and 8 havingarms bent to bea r against the back wall of the casing. It will beOl'lSQlVOfl that the retaining member 25 can be turned on its pivot 26until the shorter end of it is in line with the shaft 23, and the spring28 may be allowed to draw it partly within the shaft so that the bobbincan pass over the retaining member and into position around the shaftand then the retaining member can be -withdrawn and turned into theposition shown in Fig. 5 where it will hold the parts in place. Thebobbin holder has a portion 31 removed at one point on its circumferenceand the bearing rim 17 is also cut away at this point terminating on oneside in the sharp hook or point for engaging the loop of thread. Inoperation this cut away portion of the bobbin holder will be at the topso thatthe needle may enter it forming the loop in position to becarried againstthe hook 32 by the-hook 15 on the revolving ring. It willbe observed that the hook 15 has an. inclined surface leading down tothe contracted end of the opening 33 and thus when the loo is engaged bythis hook the thread will e carried into the 'point 33 which is acrossthe bearing groove 16 so that. the thread iscarried by' the book fromthe forward side to the rear side of the hook 32 and as the ring 12,rotates the thread will necessarily be engaged by the hook it will beobserved that the'bobbin holder being loosely mounted within the hookring would turn with it unless means are provided for preventing itsrotation and therefore I. have made use of two oscillating arms adaptedto alternately enter the openings 34, 35 more forward or inclined faceof the casing so as to prevent it from turning its the hook turns. itwill be seen by reference to Fig. 1 that these openings are in the upperportion of the casing and the arms 35 and 36 which enter i'lltli'! arepivoted at the sides of the casing extending upwardlv. and havinginwardly projecting ends entering the openings. The arms 35 and 36 arepiv oted to shafts 37. 38 which have secured to them short arms 3 40 anda link 11 is pivoted to and connects tin: ends of those arms whereby thearms 3;"; and lt? will move together. A link 1-2- is connected to thelink 41. and is pivoted at 43 to an arm carried by the rock shaft 44-.The rock shaft 44 extends-along the machine from the front to apointbelow the hollowstandard 2 and at that point has secured on it anarm 45 to which a rod 46 is pivoted, that rod having on its upper end abearing, member 47 fitting a cam 48 carried by the upper rotary shaft 6.The rotation of the shaft 6 thus reciprocates the rod it rocking theshaft 44 and to the link ctmnectious rocking the arms and 36 on theirpivots to make them alternately engage and disengage the bobbin casing,one of those arms always being in engagement. The timing of theoperation of these arms is of course so adjusted that each arm will bedisengaged at the time that the loop of thread is being carried to andpast it by the book 15. It will be. observed that the guide member 49 issecured to the under surface of the face of the machine and projectsdown around the end'of the arm 3:7 so as to guide the thread as the loopis being pulled up preventing it from beingcaught by the inwardlyprojecting end of the arm 35, this guide member being shown in the formof a Wire.

The mechanism for feeding the cloth embmlies a feed arm 50 which ispivoted at one end and which has the rat het teeth 51 at the other endadapted to proje t slightly up through an opcnin s in the work plate ofthe machine hnniediatclv below the presser foot. The feed arm is pivotedto the upper end of an 'arm 52 carried by the rock shaft 53 and it willtherefore be seen that when the shaft. 53 rocked the arm 50 will moveback and forth acro s the maehino to give the necessary feed to the(cl-1th. The shaft 53 extends along the machine to a point beneath thestandard 2 and at that. point has an arm 54 se ured to it. A link 55 ispivoted to the arm and to a link 56 at its opposite end. The link 56 ispivoted at one end to the rod 57 which rod is .held in place rigidly bya clamping screw 58 but which can be moved to ditl'orent positionsaround the we 9 within the slot (it) above the work plan o the machine.This movement ot'thc rod :1; to different positions changes the angle ofthe link 55 to the link .36, these two links operating as a toggle andthus the le erage position of the rod 37. The rod (30 is pivotod at (31at the point where links and 50 are homiccted imd this rod 60 extends uptlh'ough the hollow standard 2 having at its upper end a bearingn'lember tit ng over a i-m carried by the rotary shaft is so that as theshaft (3 turns the rod 30 will be recipro cated. The change in theleverage or angle due to the change in the position of the rod 57 willcause this reciprocation of the rod (30. I

to have a dilferent effect on the shaft 53 a so turning it diiicrentamounts according to the adjustment. It will oe observed that the rod 57car be adjusted at any time without interfering with the operation ofany parts of the machine and that the adjustment can be macle'even whilethe machine is in operation to change the feed and consequently thelength of the stitch.

The feed bar 50 must not only be reciproeatef but must be raised andlowered at the proper time to feed the cloth and the means for causingthis and fall of the feed bar is shown in Figs. 1 and l. A rock shaft 62mounted below the work plate oi: the machine adjacent the shaft 53 andit is connected by means of the arm (33 and rod 64 to a cam on therotating shaft (3 whereby it will be rocked as the shaft 6 turns. At theother end of the machine and beneath the head carrying the needle bar,the shaft 62 has secured thereto an arm ()5 which has flexible onnectionto an arm (36 secured to the feed bar 50, the arms and 66 beingsubstantially parallel and turning simultaneonsly on their pivot. Theconnecting means shown consists of a member 67 having its ends fittingin sockets in the arms 65 and on so as to maintain the spaced relationof those arms and a coiled spring 68 which is under tension tending todraw the two arms together. 1 By this airangementthe oscillation of thearm will be imparted to the arm (its and will thus give the feed arm itsup and down motion, and this operation will take place withoutinterfering with the horizontal motion imparted to the arm 50 by therock shaft 53.-

l'laving thus described the invention, What claimed is: I

3.. The combination with a rotary shaft of a revolving hook ring carriedthereby, a bob bin holder mounted in said ring, a rock sli-att, two armspivoted at their lower ends on opposite sides of said holder andextending upwardl in front of said hook ring to engage said holder onopposite sides to prevent rotation, linii connections from said rockshaft to said arms at. points near their pivots whereby a. smallmovement of said link connections will cause a much larger movement ofthe operative ends of said arms, and means for oscillating said rockshaft, periodically.

L. The combination with a rotary shaft of a revolving hook ring carriedthereby, a bobbin holder mounted in said ring, a. rock shaft,

two arms separately pivoted and adapted'to engage said bobbin holder onopposite sides alternately to prevent rotation, link arm 00nnectionsbet-ween said arms near their ivots to said rock shaft, and means forosoil ating said shaft periodically.

3. The combination with a rotor shaft of a revolvin hook ring carriedthere y, a bobbin holder mounted in said ring, a rock shaft, two armsseparately pivoted and adapted to engage said bobbin holder on oppositesides alternately to prevent rotation, link arm connections between saidarms near their pivots to said rock shaft, and means for giving saidrock shaft 3 quick oscillation once during two revolutions of said hookring.

4. In a sewin machine, the combination with the table pita, of a rotaryshaft above said plate for operating the needle bar, a rotary shaftbelow said late carrying a rotary hook ri on its en a bobbin holder witha cooperating hook within said rotary hook ring, arms adapted toalternately engage said holder on opposite sides to prevent rotation,means operated by said needle bar shaft for turning said rotary hookshaft, and independent means operated by said needle bar shaft foralternately moving said arms into and out of engagement with said bobbinholder to permit the passage of a loop of thread.

5. In a sewin machine, the combination with the table plate, of a rotaryshaft above said plate tor operating the needle bar, a rotary shaftbelow said plate carrying a rotary hook ring on its end, a bobbin holderwith a cooperating hook within said rotary hookring, arms adaptedto'alternately engage said holder on opposite sides to prevent rotation,cloth feeding mechanism below said plate, means operated by said needlebar shaft for turning said rotary hook shaft, independent means operatedby said needle bar shaft for alternately moving said arms into and outof engagement with said bobbin holder to permitthe passage of a loop ofthread, and independent means for operat-v ing said cloth fee-dingmechanism from said needle bar shaft.

In testimony whereof I a ix my signature in presence of two vitnesses.

llClL -ill D K. HOHHANN. lVi tncsses \VILLIAM L. Pianos, JAcon Barn.

